The upper part of the sternum is the main area of distribution of the first sternoclavicular joint and the sternoclavicular joint. Due to the proximity of these two joints, the shape of the sternal stalk itself is not particularly large resulting in the entirety of the upper sternum being covered by the extra-articular fibrocartilage of the sternoclavicular and first sternoclavicular joints. Once pressure pain occurs in this location, it is likely to be due to inflammation or injury of the articular fibrocartilage. In particular, periarthritis of the first sternoclavicular joint is a relatively common cause of pressure pain in this location. This is mainly because the first sternocostal joint is one of the few joints in the body that cannot be moved. Once localized compression, impact, excessive massage, etc. can lead to slight inflammation around the first thoracic rib joint, resulting in pain when localized pressure is applied.